Comparing Time Overlap

[JCScoobyRS]

I have a query that gets me all Labor Transactions for an employee for a certain day. I take the difference between the start and stop times to get the total time for that transaction. This works great until the user is doing multiple things at once. If I were to have this data:

CLOCK_IN                    CLOCK_OUT                    TOTAL
-----------------------------------------------------------------------------
3.83                              13.45                              9.62
3.83                              13.47                              9.64
10.00                            16.47                              6.47
-----------------------------------------------------------------------------
                                                                           25.73

Those are the only 3 Labor Transactions for this particular employee. If the times didn't overlap, it would work perfect as you'd get a good distinction of how long the person was actually working but since the times overlap, I am getting bad data. Can someone give me an idea of how to approach this? Since all three times overlap, I theoretically could just take the largest TOTAL time and that would be that but what if you had this:

CLOCK_IN                    CLOCK_OUT                    TOTAL
-----------------------------------------------------------------------------
3.83                              13.45                              9.62
3.83                              13.47                              9.64
10.00                            16.47                              6.47
17.25                            18.00                              0.75
-----------------------------------------------------------------------------
                                                                           26.48

? Can someone help me out? Thanks, Jeremy